The main function of pupil is at what amount of light should enter in our eyeIt mainly depends on intensity of the lightPlace where intensity of light is high pupil became smallPlace where intensity of light in low pupil get enlarge
The pupil of the eye is the black circle in the center of the iris. The whole job of the iris and pupil is to control the amount of light that gets into the eye. It\’s called a pupillary reflex, and you have probably noticed that a person\’s pupils are smaller in bright light and bigger in low light.